ABB RELION REX640 Technical Manual page 970

Protection functions
X1 zone x
Figure 542: Settings which define the line reach for phase-to-phase or three-phase
impedance measuring elements if Impedance mode Zn = "Rectangular"
In case of phase-to-earth impedance measuring elements, the line reach is defined
with:
• Resistive reach : (2⋅
• Reactive reach : (2⋅
⋅
(2 X1 zone x + X0 zone x)/3
Figure 543: Settings which define the line reach for phase-to-earth impedance
measuring elements if Impedance mode Zn = "Rectangular", forward or reverse
directionality
In case of non-directional characteristics, the reactive reach in reverse direction is
defined with the
reverse direction includes a part which is common to both forward and reverse
direction. This part is automatically calculated based on the values of the settings
R1 zone x, R0 zone 0, X1 zone x and X0 zone x . The characteristic line angle, denoted
as α, is the same for forward and reverse direction.
970
Forward
X
-R1 zone x
R1 zone x R
R1 zone x + R0 zone x )/3, (x = 1...5)
X1 zone x + X0 zone x )/3, (x = 1...5)
Forward
X
X1 reverse zone x (x = 1...5) setting. The total reactive reach in
Reverse
X
X1 zone x
R
-X1 zone x
Reverse
X
R
-(2
1MRS759142 F
Non-directional
X
α
R1 zone x R
α
-X1 reverse zone x
R
⋅
X1 zone x + X0 zone x)/3
Technical Manual
REX640